It is estimated that over 10,000 crippling knee injuries occur each ski season in Colorado, U.S.A., alone. Extrapolating worldwide there might be over 50,000 knee injuries each ski season worldwide. Great advances have been made in downhill ski bindings to automatically release during violent forward falls. Several problems exist with the best downhill ski bindings.
A serious problem is the slow, twisting backward fall. Most anterior crucia ligament (ACL) injuries occur with this type of fall. Expert skiers teaching children fall during a lesson and tear their ACL. A damaged ACL can be treated with a modern, complex, and expensive surgery called a patella tendon graft replacement for the ACL. Other body parts such as the hamstring tendon can also be used to replace the damaged ACL.
Thus, two surgeries are required. First a body part such as the patella tendon is harvested. Second the damaged ACL is removed and replaced with the harvested body part.
A good result requires six months of the replacement ACL to gain strength and function like the original ACL. About a year's physical therapy is required to regain maximum use of the leg. Two wounds must heel, without infection. Stiffness in the knee joint sometimes leads to loss of full range of motion. Atrophy of the leg muscles from the down time of surgery adds stress to the already weakened knee. Additional ACL and related injuries do occur. An average cost of one procedure with therapy is about $15,000.00.
All this misery can stem from one careless fall backwards while standing in the ski line. Following your child at 3 mph can lead to a slow backwards fall and a crippling ACL injury. Nobody has invented a working solution to this one worst injury so frequently caused by a careless moment on downhill skis.
One new attempt to solve this problem is the Lange® boot rearward pivot ankle segment of the boot. A pre-set backward force will release the ankle segment of the boot rearward. However, the boot is still locked into the ski binding. Only twelve pounds of twisting torque on the foot is required to tear an ACL. The Lange® boot solution does not address the release of rotational force on the knee. It addresses the release of a rearward force by the boot on the back of the skier's calf. It is unknown if this system will reduce ACL injuries.
A large portion (perhaps half) of all ACL injuries occur at slow speeds falling backwards. Therefore, a couple of seconds of reaction time exists for a trained skier (either novice or expert) to push an emergency release button on his ski pole handle and totally eject from his skis. By the time the skier hits the ground, he's out of his skis without exerting any rotational torque to his knees. Properly trained skiers using the present invention can reduce the risk of ACL injury by a large percent, perhaps even half. This could mean 25,000 fewer worldwide ACL injuries a year, and a much safer sport overall.
Other uses for this emergency release system (also called a bail out™ system) include easy release for beginners so they can spend less time learning to stand up, and more time skiing. Upside down skiers in a tree hole can quickly release and quickly get out of a dangerous situation.
The basic principle of the present invention is to mount the heel and/or toe release segment of a ski binding on a short track. Pushing the release button energizes a stored force on the ski to move the heel and/or toe binding along the track to a position larger than the ski boot. The result is a size 10 boot in a size 12 binding. The skier is instantly free of his skis.
To remount the skier resets his binding to the loaded and properly sized position, steps in, and skis as usual.